"тетра-" meaning in Russian

{
  "etymology_templates": [
    {
      "args": {
        "1": "ru",
        "2": "grc",
        "3": "τέτταρες",
        "4": ""
      },
      "expansion": "Ancient Greek τέτταρες (téttares)",
      "name": "der"
    },
    {
      "args": {
        "1": "grc",
        "2": "τέσσαρες",
        "3": "",
        "4": "four"
      },
      "expansion": "τέσσαρες (téssares, “four”)",
      "name": "m"
    }
  ],
  "etymology_text": "From combining form of Ancient Greek τέτταρες (téttares), τέσσαρες (téssares, “four”).",
  "forms": [
    {
      "form": "tetra-",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ru",
        "2": "prefix"
      },
      "expansion": "тетра- • (tetra-)",
      "name": "head"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Russian entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "tetra-"
      ],
      "id": "en-тетра--ru-prefix-i3YIyLny",
      "links": [
        [
          "tetra-",
          "tetra-"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[tʲɪtrə]"
    },
    {
      "ipa": "[tɨtrə]"
    }
  ],
  "word": "тетра-"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "ru",
        "2": "grc",
        "3": "τέτταρες",
        "4": ""
      },
      "expansion": "Ancient Greek τέτταρες (téttares)",
      "name": "der"
    },
    {
      "args": {
        "1": "grc",
        "2": "τέσσαρες",
        "3": "",
        "4": "four"
      },
      "expansion": "τέσσαρες (téssares, “four”)",
      "name": "m"
    }
  ],
  "etymology_text": "From combining form of Ancient Greek τέτταρες (téttares), τέσσαρες (téssares, “four”).",
  "forms": [
    {
      "form": "tetra-",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ru",
        "2": "prefix"
      },
      "expansion": "тетра- • (tetra-)",
      "name": "head"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        "Russian 2-syllable words",
        "Russian entries with incorrect language header",
        "Russian lemmas",
        "Russian prefixes",
        "Russian terms derived from Ancient Greek",
        "Russian terms with IPA pronunciation"
      ],
      "glosses": [
        "tetra-"
      ],
      "links": [
        [
          "tetra-",
          "tetra-"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[tʲɪtrə]"
    },
    {
      "ipa": "[tɨtrə]"
    }
  ],
  "word": "тетра-"
}